The day honors Martin Luther King, Jr. on Jan. 21 and is part of President Barack Obama's United We Serve initiative. Clinton will reportedly join celebrities like Eva Longoria, Ben Folds and Angela Basset to headline a service summit on the National Mall on Jan. 19. Their example is supposed to encourage others around the country to sin up for the National Day of Service.

"When I was growing up, both my parents and grandparents instilled a commitment to service in me. They taught me that helping our neighbors and serving our community were essential parts of being a good citizen and a good person," she says in a statement. "Think about how much good we can all do if everyone who pitches in this weekend keeps up that commitment throughout the year."